1 Department of Mathematical Sciences, Isfahan Uinversity of Technology, Isfahan 84156-83111, Iran

2 Department of Mathematics, Faculty of Sciences, Shiraz University, Shiraz 71454, Iran

3 Department of Mathematics, Islamic Azad University, Central Tehran Branch, Tehran 14676-86831, Iran


In this paper, we investigate the relation between L-projections and conditional expectations on subalgebras of the Fourier Stieltjes algebra B(G), and we will show that compactness of G plays an important role in this relation.


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